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The first bidirectional study to examine drinking’s role in college students with post-traumatic stress disorder (PTSD) has found the risks of heavy drinking to be markedly higher among those with the condition.

To the select few who remain unaware, collegiate social life practically hinges on alcohol consumption. Drinking unites the otherwise disparate groups within large, anonymous student bodies. According to the National Institute on Alcohol Abuse and Alcoholism, approximately four out of every five college students drink alcohol. More problematic, 90 percent of drinking done under age 21 is binge drinking, says the Centers for Disease Control and Prevention. Now researchers from the University of Buffalo argue this climate may be disastrous for the nine percent of students with PTSD who are more likely to temporarily numb their pain through drinking, yet plunge themselves deeper into the disorder in the long-run.

This vicious cycle concerns University researchers, who claim that PTSD sufferers may fall to a wide range of triggers — violence, drug use, sexual assault, and self-harm all tend to correlate highly with heavy drinking. Among people with PTSD, these risks intensify even more. Dr. Jennifer Read, associate professor of psychology at the University at Buffalo and study leader, said her team’s study is the first to formally connect the two, which until lately have only existed as conjecture.

“We show that alcohol use and associated problems are linked over time to an exacerbation in PTSD symptoms, and that PTSD symptoms show a similar effect on alcohol consumption,” Read explained in a news release. “Each affects the other. As such, both PTSD and heavy drinking are risk factors for one another, each with implications for the other over the course of college.”

Read and her colleagues looked at 486 students as they made their way into college and then checked in at 11 additional points over the following three years. They found that the students showing symptoms of PTSD not only fell deeper into their condition, but put themselves at risk for alcoholism. According to the U.S. Department of Veterans Affairs, about 5.2 million adults have PTSD during a given year. Younger people and those who heavily consume alcohol face a greater risk for adverse response to trauma.

Read hopes the study can help influence policy changes on college campuses, as detecting a current or impending liability allows trained personnel to intervene before anything damaging happens. What’s more, understanding that PTSD can arise from sources other than serving in the military — such as childhood trauma within a family and otherwise — can allow these assisting forces to better monitor at-risk students.

“This information is useful and perhaps imperative for those who assist students dealing with these problems,” Read explained. One 2012 study Read and her colleagues conducted found that the first year of college is critical in determining how posttraumatic students fair in terms of alcohol and drug use. Again, the team pushed for greater support systems that can target, and help rehabilitate, students who may be a danger to themselves or others.

“Interventions that offer support and resources to students entering college with PTSD may help to ameliorate problem substance use,” the team wrote, “and may ultimately facilitate a stronger transition into college and beyond.”